The Waterborne Symposium 2025

Abstract
"Microbial contamination of paint and coating products can have adverse effects on the product, such as offensive odors, discoloration, or viscosity changes. Although preservatives (biocides) are available as additives to prevent the proliferation of microbial growth, manufacturing controls should be implemented to prevent the contamination in the final product. Robust cleaning processes and other manufacturing controls can be designed to provide microbial control for equipment product-contact surfaces, preventing microbial contamination of the product. A thorough understanding of the raw materials, formulation, manufacturing process, and other manufacturing characteristics will help identify potential sources of contamination and guide the development of the contamination controls needed in manufacturing. Designing processes that can address both cross-contamination and microbial contamination on equipment surfaces would be beneficial for production efficiencies while producing quality products with a longer shelf life.

This presentation proposes a holistic approach for controlling microbial contamination through the implementation of effective cleaning processes and other cleaning-associated activities. Current regulatory trends limit manufacturers to the use of certain preservatives, which may not be as effective as some of the legacy additives used in the past. This promotes a need for the implementation of preventive controls for microbial contamination introduced during the process and less reliance on the use of preservatives in the product. A cleaning process can be designed through a formal risk assessment process where critical process controls are implemented to mitigate microbial contamination risks identified that may impact a product’s critical quality attributes. There are multiple factors that play into the design of an effective and efficient cleaning process: control of water and raw material quality, selection of adequate cleaning agents, equipment storage conditions, equipment preventative maintenance procedures, and the critical controls of the cleaning process itself. When adequate controls are implemented, the cleaning process and other preventive measures discussed in this presentation can control microbial contamination on equipment and, subsequently, the final product."